If all you want to do is to see if a provider or firewall is blocking the
protocol, use something like 'Laurent Constantin's network library (lcrzo)'
located at http://www.laurentconstantin.com/en to create your own IP
packets and sniff/log on the receiving end to see if it actually got
through.

Would it be possible to give me some ideas on testing to see if GRE
protocol
is getting from A to B?

Thanks for all your help.

Mark
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